Morin Elyse L, Hadj-Bouziane Fadila, Stokes Mark, Ungerleider Leslie G, Bell Andrew H
Laboratory of Brain and Cognition, NIMH/NIH, Bethesda, MD, USA.
Oxford Centre for Human Brain Activity Department of Experimental Psychology, University of Oxford, Oxford, UK.
Cereb Cortex. 2015 Sep;25(9):3036-45. doi: 10.1093/cercor/bhu099. Epub 2014 May 16.
Faces convey information about identity and emotional state, both of which are important for our social interactions. Models of face processing propose that changeable versus invariant aspects of a face, specifically facial expression/gaze direction versus facial identity, are coded by distinct neural pathways and yet neurophysiological data supporting this separation are incomplete. We recorded activity from neurons along the inferior bank of the superior temporal sulcus (STS), while monkeys viewed images of conspecific faces and non-face control stimuli. Eight monkey identities were used, each presented with 3 different facial expressions (neutral, fear grin, and threat). All facial expressions were displayed with both a direct and averted gaze. In the posterior STS, we found that about one-quarter of face-responsive neurons are sensitive to social cues, the majority of which being sensitive to only one of these cues. In contrast, in anterior STS, not only did the proportion of neurons sensitive to social cues increase, but so too did the proportion of neurons sensitive to conjunctions of identity with either gaze direction or expression. These data support a convergence of signals related to faces as one moves anteriorly along the inferior bank of the STS, which forms a fundamental part of the face-processing network.
面孔传达有关身份和情绪状态的信息，这两者对我们的社交互动都很重要。面孔加工模型提出，面孔的可变与不变方面，特别是面部表情/注视方向与面部身份，由不同的神经通路编码，但支持这种分离的神经生理学数据并不完整。我们记录了沿着颞上沟（STS）下缘的神经元的活动，同时猴子观看同种面孔和非面孔对照刺激的图像。使用了八只猴子的身份，每只猴子呈现三种不同的面部表情（中性、恐惧咧嘴和威胁）。所有面部表情都以直视和回避注视两种方式展示。在STS后部，我们发现约四分之一对面孔有反应的神经元对社交线索敏感，其中大多数仅对这些线索中的一种敏感。相比之下，在STS前部，不仅对社交线索敏感的神经元比例增加，而且对身份与注视方向或表情的联合敏感的神经元比例也增加了。这些数据支持了随着沿着STS下缘向前移动，与面孔相关的信号会汇聚，而STS下缘是面孔加工网络的一个基本组成部分。
